[rab] No, you only had about half of them. There are a full *eight* main chords at the start of each of the first eight bars (which you gave a "plang" to), the first seven each having a "chong" on the lowest bass F of the piano halfway through the bar...

And now a piece that you might be able to guess, just from the rhythm that runs through the entire piece as a background, which I'll give two bars in italics
TUM-tiddly-UM-tiddly-UM-tum
TUM-tiddly-UM-tiddly-UM-tum...
Deeeeeeee, da-da-doo-da-da-da dee, da-da-deeeeeeeeee - Da-da doo-da-da-da-deeee.....

[JLE] Now that (number 24) is Ravel's Bolero.

*grin*

updating:
1. Bob the dog - ISIHAC Theme 2. Chalky - Coronation Street 3. HB - Some Mothers Do 'Ave 'Em 4. Raak - Thunderbirds 5. Kim - The Archers' Theme 6. rab - Roobard and Custard 7. Bob the dog - Pomp and Curcumstance, Edward Elgar 8. Lib - Blind Date 9. ZK - Dangermouse 10. penelope - Blue Peter 11. Watty - Porridge 12. Kim - Tom & Jerry [Fred Quimby version] 13. Herr Bratsche - Monty Python 14. Raak - Star Trek 15. Bob the dog - Dr Who 16. rab - Have I Got News For You 17. Darren - Bergerac 18. Chalky - The Sweeney 19. Darren - Rentaghost 20. rab's plang-chonger - Rachmaninov's Piano Concerto number 2 in C minor. 21. Dazed - Blackadder. 22. Darren's dum-diddliddle-dum-dit-dit ? 23. JLE - Mahler's Symphony No.2 "Resurrection" 24. JLE - Ravel's Bolero

I reckon Watty and Darren should be choosing the next two tunes , although Darren's No 22. [80's TV] has yet to be guessed

Clues? New tunes?

OK, here's 25 and it's 90s TV.

RattattattattattattATT!!
dada duhhhh, dada duhhhhh, dada duhhhhh da-da.
dada duhhhh, dada duhhhh, dada deeee da-da.
dada duhhhh, dada duhhhh, dada duhhh da-da,
da-daaaaa, da-daaaa, da-daaaaa, da-da.
(repeat from second line)
dadada daaaa-daaa-daa-daaaa, daaa-daaa-daaa-daaa,
dum-da-daaaa-da daaaa-daaaa-daaa-da,
dum-da-daaa-daaa daaaa-daaaa-daaa-daaa DAAAAAAA
(repeat first bit again)

Does anyone want a clue to number 22?